در منطقه كرج avena ludoviciana Dur( و يولاف وحشي )Goldbachia Laerigata DC.( در مقابل علف هاي هرز با تاكيد بر ناخنك )Triticum aestivum L( ارزيابي قدرت رقابت برخي از ژنوتيپ هاي گندم زمستانه

Evaluation of competitive ability of some winter wheat(Triticum aestivum L.) genotypes against weeds with attention to GoIdbachia Iaevigata DC. And Avena Iudoviciana Dur. in Karaj

In order to study of competitive ability of winter wheat genotypes against weeds, a three year trail was conducted as preliminary (1999) and complementary (2000-2001) experiments at weed research station of Plant Pests and Diseases Research Institute in Karaj. The preliminary experiment was carried out in randomized completed block design (RCBD) with four replications in a factorial arrangement of treatments. Treatments included twelve genotypes of wheat at two levels (weedy or weed free). The results of preliminary experiment showed that wheat genotypes 6618, M-75-13, M-75-I5 were more competitive (MC) and Alamoot, Ghafghaz and M-75-5 were less competitive (LC) genotypes. Avena ludoviciana and Goldbachia laviegata were showed to be the dominant broad- and narrow-leaf weeds in the complementary experiment. The complementary experiment was conducted as a RCBD with four replications. Treatments included six wheat genotypes at three weedy levels (Goldbachia laviegata, Avena ludoviciana and weed free control). The results of complementary experiment indicated that using competitive index (Cl), weed biomass and grain yield in pure and mixed stand. lines 6618 and M-75-5 were as MC and LC, respectively Results indicated that CI was a suitable index for determination of MC from LC wheat genotypes. The comparison of morphological and physiological characteristics of lines 6618 and M-75-15 can be used as an important criterion for determination of competitive ability of wheat against weeds in breeding programs.